Scaffold.



.G. 5., W.'S. & P. 0. THRALL.

SOAFFOLD.

APPLICATION FILED JULY 8, 1914.

1, 1 1 3,509. Patented Oct. 13,1914.

i 17 +1 7 ll 4 I D 1 11 UINTTED STATES PATENT OFFICE.

GEORGE E. THRALL, WILLIAM S. THRALL AND PERRY O. THRALL. OF WASHINGTON, DISTRICT OF COLUMBIA.

soArroLn.

Specification of'Letters Patent.

Patented Oct. 13, 1914.

Application filed July 8, 1914. Serial No. 849,778.

To all whom it may concern:

lie it known that we, GEORGE E. THRALL, \Vnaaaii S. Tnnann, and PERRY O. THRALL, citizens of the United States, residing at Washington, in the District of Columbia, have invented certain'new and useful Improvements in Scaifolds, of which the following is a specification.

This invention relates to scaffolds, and more particularly to means for supporting a ladder in upright position to adapt It 'to sustain scalt'olding in working position.

The primary object of the invention is, to provide novel means for supporting ladders, or like vertical scafi'old supports in proper juxtaposition to a window, acolumn or other support.

The invention also includes means for securing planks or staging to the rounds of a ladder.

The construction of the improvement will be fully described hereinafter in connection with the accompanying drawing, which forms a part of this specification, and its features of novelty will be set forth and ,defined in the appended claims.

In the drawing:

Figure l is a top plan view of a ladder .clamp embodying the invention. Fig. 2 is a fragmentary perspective view showing the clamp in posit-ion upon a window frame. Fig. 3 is a top plan view of a modified construction of the device adapted for use in connection with a column on other circular support. Fig. 4 is a side elevation of a portion of a ladder showing the ladder brace and staging partly in section, and Fig. 5 is a detail longitudinal section of the board shown in Fig. 1 with its U-shaped securing clamp.

The referencenumeral 1 designates a window frame of the usual construction, and 2 an ordinary ladder supported in front of the window in upright position by the novel means shown. comprising a clamp consisting of two parallel arms 3 from the inner ends of which project diverging arms 4 connected by a horizontal brace 5 and having their inner ends 6 in parallel relation to be clamped against the inner sides of the window frame as shown in Fig. 2 by suit-.

able means, the means here shown comprising two extensible bars 8 having their inner ends 9 screw threaded for attachment to a.

turn-buckle 10. The outer ends 11 of the bars '8 are squared to extend through correspondingly shaped guides 12 formed in the flattened ends (3 of the arms 3, and adapted to be automatically secured thereto by clamping devices as shown at 13. The parallel outer ends of the arms .3 embrace the ladder 2 on opposite sides thereof, and are detachably connected to the ladder by cross-bolts 14.

The board or staging 15 rests upon the rounds 16 of the ladder as shown in. Figs. 4 and '5, and the ends of the board are secured upon the rounds by U-shaped clamps 17 extending through openings in the board, and embracing the ladder round as best shown in Fig. 5.

It will be apparent that the turn-buckle 10* permits of the adjustl'nent of the bars 8 to fit windows of different width, and that the device is readily detachable from both the 'la'dder and window-frame.

Fig. Bishows a modified embodiment of the invention in which two semi-circular clamping arms 18 and-19 are employed to ada'pt'the device to be secured upon a round column or like circular support, instead of to the sides of a ,window frame. The bars 8 are formed integral. with the member 19 and are recessed as at 20 to receive the ends 21 of the other clamping member 18, said cndsbeing detachably connected to the bars 8 by securing devices 22.

The improvement affords means for readily building a scaffold or staging Whereever required, and by reason of the ready removability of all of the securing devices the scaffolding may be ouicldy'atiaken down.

Having fully described our invention, what we claim and desire to secure by Letters Patent is:

1. A ladder support for scaffolding comprising a pair of parallel arms, having diverging inncr ends adaptedto be secured to a support. and means for detachably securing said arms on opposite sides of a ladder.

2. The combination with a window frame and a ladder, of a pair of parallel arms em- .bracing opposite sides of the ladder, and

3. The combination With a Window frame and a ladder, of a clamping device comprising parallel arms embracing opposite sides of the ladder and having diverging inner ends provided with guides, longitudinally adjustable bars extending through said guides, devices for securing saidbars within said guides, and means for detachably securing the arms together.

In testimony whereof we affix our signa- 10 tures in presence of two Witnesses.

Witnesses EDWARD J. NEWCOMB, ADA V. W001).

Copies of this patent may be obtained for five cents eaoh, by addressing the "Commilsioner of Patents,

Waslflnztony D. G. I 

